Ethological Explanations Flashcards
What is ethology?
the study of animal behaviour in natural settings.
What is the Ethological explanation?
studying aggression in nonhuman animals and extrapolate findings to humans because we are all subject to the same forces of natural selection.
What are the key elements in the ethological approach?
- Aggression is an instinct
- It is adaptive and mostly genetically determined.
How is aggression adaptive?
- Reduces Competition pressure
- Helps to establish dominance hierarchies.
How does aggression reduce competition pressure?
- A ‘defeated’ animal is rarely killed, but rather is forced to establish territory elsewhere.
- This means that members of a species spread out over a wider area and have to discover resources in a different place, reducing competition
How does aggression help to establish dominance hierarchies? Application to humans?
- Male chimpanzees use aggression to climb their troop’s social hierarchy. Dominance gives them special status (mating rights)
- researchers studied groups of young children and observed how aggression played an important role in the development of dominance hierarchies
What is ritualistic aggression?
- example of aggression that is adaptive
A ritual is a series of behaviours carried out in a set order.
What are ritualistic signals?
- Lorenz observed that fights between animals of the same species produced little actual physical damage and consisted of a prolonged period of ritualistic signalling
- showing claws and teeth, facial expressions of threat
What are appeasement gestures?
- Lorenz pointed out that intra-species aggressive confrontations end with ritual appeasement displays.
- These indicate acceptance of defeat and inhibit further aggressive behaviour preventing any damage to the loser.
Eg wolf exposing jugular vein
Why are appeasement gestures adaptive?
if every aggressive encounter ended with the death of one of the combatants, that could threaten the existence of the species.
What are IRMs (Innate releasing mechanisms) and FAPs (fixed action pattern) ?
Animals have a built-in neural structure (a network of neurons) which, when exposed to specific stimulus will cause the release of an automatic behavioural response (a fixed action pattern).
What are the 6 features of FAPs?
- Stereotyped, or relatively unchanging sequences of behaviours.
- Universal, because the same behaviour is found in every individual of a species.
- Unaffected by learning, the same for every individual regardless of experience.
- Ballistic, once the behaviour is triggered it follows an inevitable course and cannot be altered before it is completed.
- Single-purpose, the behaviour only occurs in a specific situation and not in any other.
- A response to an identifiable specific sign stimulus (or, if it involves communication between members of the same species, it is known as a releaser)
What animal was used to study FAPs and why?
- Male sticklebacks
- because highly territorial during the mating season and develop a red spot on their underbelly.
- If another male enters their territory, a sequence of highly-stereotyped aggressive behaviours is initiated. Due to sign stimulus of red spot
What is the procedure of Tinbergen’s study?
Male sticklebacks were presented with a series of wooden models of different shapes.
What were the findings of Tinbergen’s study?
- Regardless of shape, if the model had a red spot the male stickleback would aggressively display and even attack it.
- But if there was no red spot, there was no aggression.
- these FAPs were unchanging and once triggered it ran its course to completion
What research to support aggression being innate?
P: One strength is support from research related to genetics and evolution.
EE: There is a lot of evidence for the genetic basis for aggression. E.g. Brunner et al’s study (1993) showed that one gene (the MAOA-L gene) is closely associated with aggressive behaviour in humans.
Twin and adoption studies also showed that there is a significant genetic component to aggression in humans. These lines of research point towards an innate basis to aggressive behaviour.
L: This suggests the ethological approach is correct in claiming that aggression is genetically determined, heritable and adaptive.
What is a counterpoint to research supporting aggression being innate?
P: counterpoint
EE: However, aggressive behaviour differs from one culture to another, sometimes even within the same country. Nisbett (1993) found that one type of homicide (reactive aggression) was more common amongst white men in the southern United States than in the northern states. Reactive aggression is a response to threats from someone else. Nisbett concluded that the difference was caused by a ‘culture of honour’ in the southern US. This culture is less prevalent in the north, which is why rates are lower there. So this kind of aggressive behaviour comes from a learned social norm rather than being innate.
L: Therefore culture can override innate predispositions, which is hard for ethological theory to explain.
What is a limitation of ritualistic aggression?
P: One limitation is that aggression against members of the same species is not just ritualistic
EE: Jane Goodall (2010) observed a ‘four-year war’ during which male
chimps from one community killed all the members of another group. They did this in a systematic way. On some occasions, a victim would be held down by rival chimps while others hit it in an attack lasting many minutes. The violence continued even when victims offered appeasement signals. So, the signals did not inhibit the aggressive behaviour of the attackers as predicted by the ethological explanation.
L: This challenges the ethological view that same-species aggression has evolved into a self-limiting and relatively harmless ritual.
What is limitation of FAPs?
P: One limitation of FAPS is that Lorenz’s original view of FAPs is outdated.
EE: Lorenz saw FAPs as innate and unchanging. But the psychologist Hunt (1973) has pointed out that FAPs are actually greatly influenced by environmental factors and learning experiences. E.g. The duration of each behaviour in a sequence varies from one individual to another, and even in the same individual from one encounter to another. Because they are modifiable by experience, many ethologists now prefer the term ‘modal behaviour pattern’ to reflect this.
L: Therefore patterns of aggressive behaviour are much more flexible
than Lorenz thought, especially in humans.
What is a limitation of the ethological explanation?
P: One limitation of the ethological explanation is that it is deterministic.
EE: Ethologists argue is innate and mostly genetically determined.
An important implication of this view is that humans will inevitably be aggressive and fight each other (e.g. in wars). Once it is triggered it follows an inevitable course and cannot be altered before completion. However, other approaches in psychology (e.g. cognitive) suggest that aggression is not inevitable because it is more under rational control than instinctive. This is because humans have the capability to think about their behaviour and assess its consequences. It is also affected by learning experiences (cultural & social norms - ‘culture of honour’ in US South) and can override innate predispositions and make aggression far from inevitable.
L: Therefore aggression may have instinctive elements but in humans it is more strongly influenced by cognitive and social factors.
